.footer {
  width:99%;
  position:absolute;
  bottom:0;
  margin:0 auto;
}
  
.collapsible {
  background:#2a2a2a;
  color:#fff;
  cursor: pointer;
  padding: 8px;
  width: 150px;
  border: none;
  text-align: center;
  outline: none;
  font-size: 15px;
  border-top-left-radius:10px;
  border-top-right-radius:10px;
}

/* Add a background color to the button if it is clicked on (add the .active class with JS), and when you move the mouse over it (hover) */
.active, .collapsible:hover {
  background-color: #ccc;
}

/* Style the collapsible content. Note: hidden by default */
.content {
  padding: 8px;
  width: 100%;
  display: none;
  overflow: hidden;
  background-color: #f1f1f1;
}